Buggy code:
public class Form extends WebMarkupContainer implements IFormSubmitListener { public abstract static class ValidationVisitor implements FormComponent . IVisitor { public Object formComponent ( IFormVisitorParticipant component ) { } public abstract void validate ( FormComponent formComponent ) { } } class FormDispatchRequest extends Request { private final ValueMap params = new ValueMap ( ) ; private final Request realRequest ; private final String url ; public FormDispatchRequest ( final Request realRequest , final String url ) { } public Locale getLocale ( ) { } public String getParameter ( String key ) { } public Map getParameterMap ( ) { } public String [ ] getParameters ( String key ) { } public String getPath ( ) { } public String getRelativePathPrefixToContextRoot ( ) { } public String getRelativePathPrefixToWicketHandler ( ) { } public String getURL ( ) { } } public static final String METHOD_GET = "get" ; public static final String METHOD_POST = "post" ; private static final short FLAG_SUBMITTED = FLAG_RESERVED1 ; private static final Logger log = LoggerFactory . getLogger ( Form . class ) ; private static final long serialVersionUID = 1L ; private static final String UPLOAD_FAILED_RESOURCE_KEY = "uploadFailed" ; private static final String UPLOAD_TOO_LARGE_RESOURCE_KEY = "uploadTooLarge" ; private Button defaultButton ; private Object formValidators = null ; private String javascriptId ; private Bytes maxSize = null ; private boolean multiPart = false ; public Form ( final String id ) { } public Form ( final String id , IModel model ) { } public void add ( IFormValidator validator ) { } public void remove ( IFormValidator validator ) { } private final int formValidators_indexOf ( IFormValidator validator ) { } private final IFormValidator formValidators_remove ( IFormValidator validator ) { } private final IFormValidator formValidators_remove ( int index ) { } public final void clearInput ( ) { } public final void error ( String error , Map args ) { } public final IFormSubmittingComponent findSubmittingButton ( ) { } public final Button getDefaultButton ( ) { } public final CharSequence getJsForInterfaceUrl ( CharSequence url ) { } public Bytes getMaxSize ( ) { } public Form getRootForm ( ) { } public String getValidatorKeyPrefix ( ) { } public final boolean hasError ( ) { } public boolean isRootForm ( ) { } public final boolean isSubmitted ( ) { } public boolean isVersioned ( ) { } public final void loadPersistentFormComponentValues ( ) { } public final void onFormSubmitted ( ) { } public boolean process ( ) { } public void removePersistentFormComponentValues ( final boolean disablePersistence ) { } public final void setDefaultButton ( Button button ) { } public void setMaxSize ( final Bytes maxSize ) { } public void setMultiPart ( boolean multiPart ) { } public final Component setVersioned ( final boolean isVersioned ) { } public final void visitFormComponents ( final FormComponent . IVisitor visitor ) { } public final void visitFormComponentsPostOrder ( final FormComponent . IVisitor visitor ) { } private boolean anyFormComponentError ( ) { } private void dispatchEvent ( final Page page , final String url ) { } private void formValidators_add ( final IFormValidator validator ) { } private IFormValidator formValidators_get ( int index ) { } private int formValidators_size ( ) { } private void inputChanged ( ) { } private void persistFormComponentData ( ) { } protected void appendDefaultButtonField ( final MarkupStream markupStream , final ComponentTag openTag ) { } protected void beforeUpdateFormComponentModels ( ) { } protected void delegateSubmit ( IFormSubmittingComponent submittingButton ) { } protected final String getHiddenFieldId ( ) { } protected final String getJavascriptId ( ) { } protected String getMethod ( ) { } protected boolean getStatelessHint ( ) { } protected IValuePersister getValuePersister ( ) { } protected boolean handleMultiPart ( ) { } protected void internalOnModelChanged ( ) { } protected final void markFormComponentsInvalid ( ) { } protected final void markFormComponentsValid ( ) { } protected void onComponentTag ( final ComponentTag tag ) { } protected void onComponentTagBody ( final MarkupStream markupStream , final ComponentTag openTag ) { } protected void onDetach ( ) { } protected void onError ( ) { } protected void onRender ( final MarkupStream markupStream ) { } protected void onSubmit ( ) { } protected final void updateFormComponentModels ( ) { } protected void validate ( ) { } protected final void validateComponents ( ) { } private boolean isFormComponentVisibleInPage ( FormComponent fc ) { if ( fc == null ) { throw new IllegalArgumentException ( "Argument<seq2seq4repair_space>`fc`<seq2seq4repair_space>cannot<seq2seq4repair_space>be<seq2seq4repair_space>null" ) ; } Component c = fc ; Component last = fc ; while ( c != null ) { if ( ( c . isRenderAllowed ( ) ) && ( c . isVisible ( ) ) ) { last = c ; c = c . getParent ( ) ; } else { return false ; } } <START_BUG> return last == ( this ) ; <END_BUG> } protected final void validateFormValidator ( final IFormValidator validator ) { } protected final void validateFormValidators ( ) { } private class FormValidatorRemovedChange extends Change { private static final long serialVersionUID = 1L ; private final IFormValidator removed ; public FormValidatorRemovedChange ( final IFormValidator removed ) { } public void undo ( ) { } } }

Fix:
return last == ( this . findPage ( ) ) ;